public class Functions {

	public static int faculty(int n){
		int a=n;
		if(n==0)return 1;
		for(int i=1; i<n; i++){
			a=a*i;
		}return a;
	}
	
	
	public static void main(String[] args) {

		int n=0;
		System.out.println("The faculty of "+n+" is "+faculty(n));
	}

}
